I found the mixture at the local Kindergarten. After all, it only costs less than one Euro for 2 Kilos of modelling material. Some folks say, it tends to collect moisture from the surrounding after drying, so I might have to seal it with a suitable varnish.
At the moment I am trying to find suitable lighting. With room / exibition light it is too dark and too grey inside of an APA Box. On the other hand, bright flood light is not really something, you´d expect in a cave.
I suppose, light and colour design will keep me busy for a while. One thing is certain, it is almost impossible, to show the beauty of a cave on photographs. Whenever you change the light, colours and shadows are changing as well in a dramatic way.
Meanwhile an earthquake broke away part of one of the cave´s walls.
The inside of the APA Box looks a lot larger now.